Problem Statement Generating station located in Hyderabad is powering four types of load in the Nawabshah region through the transmission line (line impedance 0.161+j0.109 /km) with the pair of single-phase transformers (230/11000 V & 11000/230 V) at either end. The series resistance of the transformer is 0.01 pu and Series reactance is 0.08 pu. The first load is a flour milling company, which absorbs an average active power of 250 kW and the company has maintained the power factor to 0.8 Lagging. The time of operation for this company is 08-00 am to 4-00 pm. The second load is a small textile mill, working from 10- 00 am to 06-00 pm while maintaining the power factor of 0.87 lagging and consuming 200 kVAs. On the other hand, the third load consists of the group of laundry shops (where clothes irons are used for pressing clothes on large scale), absorbing real power of 20 kW and are operational from 12-00 pm to 08-00 pm. Similarly, the last load is a toy manufacturing unit, consuming the apparent power of 300 kVA while maintaining a power factor of 0.85 lagging for a time duration of 8 hours per day, from 02-00 pm to 10-00 pm. The electrical frequency of all the loads is fixed to be 50 Hertz. You are hired as a design engineer to propose the VA ratings of the transformers along with the type of transformer that you are going to use. Justify the type of transformer that you are selecting for the said scenario, it may be an autotransformer or an ordinary transformer keeping in view the financial perspectives of your selection along with technical ones. While designing the transformer, also take the following factors into account. Total demand for the load Overall weather of the region Height relative to sea level

Note: National Electric Code or NFPA 70 standards, transformer kilovolt-ampere should be de- rated by 8% for each 10C above 40C (when air-cooled for a dry-type transformer) and by

0.3% for every 330 feet over 3,300 feet altitude). Tasks 1) To propose adequate power ratings for all the transformers used in the system.